ES2558866T3 - Composite sheet with a coating based on polyvinylidene chloride, procedure for its preparation and use - Google Patents

Abstract

Composite sheet (1) comprising a support sheet (11), adhesion promoting agent (10), a PVDC sheet (9) and a coating (8) applied on the PVDC sheet (9) based on poly (vinylidene chloride), characterized in that particles (12) of polymers, natural substances, modified natural substances, inorganic materials or mixtures thereof are contained in the polyvinylidene chloride of the coating (8), the density of the particles (12) is in the range of 0.1 to 2.0 g / cm3, the average diameter of the particles (12) is 1 to 100 μm, a certain number of the particles (12) protrude from the coating (8 ) and the largest particle diameter is equal to / greater than the thickness of the coating (8).

Description

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DESCRIPTION

Composite sheet with a coating based on polyvinylidene chloride, a procedure for its preparation and use

The invention relates to a composite sheet based on polyvinylidene chloride, a process for the production of a composite sheet and its use.

Multi-layered compounds, hereinafter referred to as "composite elements" or "composite sheets", are used inter alia for the packaging of food and pharmaceutical products. Often a coating of the sheet or upper layer of such composite elements is carried out with dispersions of polymers or copolymers of vinylidene chloride. For example, for the packaging of pharmaceutical products, PVC sheets or PVC-PE composite sheets with copolymer dispersions of vinylidene chloride are coated and then processed in a thermoforming process until blisters are then loaded with the packaging product and they are closed with an aluminum foil or a thin sheet of polymer cap by sealing. Vinylidene chloride monomers polymerize the mayone of the time with methacrylates, acrylates, vinyl chloride or acrylonitrile until copolymers. The purpose of the vinylidene chloride copolymer coating is the formation of a sealable coating and / or the formation of a barrier layer for water vapor, oxygen and aromas.

Vinylidene chloride copolymer dispersions form plastic films that in the fresh state, in particular when they do not contain any additional wax or lubricant additive, have on the one hand a tendency to adhere, that is, an inclination to adherence to a smooth surface, such as the next winding of a roll of sheet and, on the other hand, very high static and sliding coefficients of friction with respect to metals, plastics and natural substances. The coefficients of friction certainly decrease after the surface of the PVDC coating has hardened by the crystallization that begins and progresses more or less rapidly. However, a tendency to adhere to parts of machines or low slip properties during filling with the packaging items, in particular with gelatin capsules, is maintained. There is also a tendency towards unwanted adhesion of the PVDC layer to hot machine parts, such as, for example, in the hot zone of thermoforming machines.

The tendency for adhesion leads to the fact that after rolling the composite sheet onto the soft PVDC surface, transfer images are produced that occur due to contact with the next winding of the sheet. If the surface of PVDC is very smooth, as is the case in application systems with weft cylinders or lines currently used for coating with dispersion of PVDC in case no countermeasures have been adopted, due to the air introduced in the winding larger areas with a bright surface are produced, since contact with the next winding is avoided due to air bubbles included. To the side there are areas with a matt surface that have contact with the next winding and in which, consequently, transfer images are produced. The transfer images themselves do not lead to any technical deficiency in the PVDC coating, however, such composite elements are often not accepted for aesthetic reasons. In some cases, however, in the case of PVDC coated sheets, undesired deformation may also occur and, where appropriate, leads to subsequent defects of the sheets due to air bubbles introduced into the winding.

As a general rule, a reduction of this effect of air inclusion is achieved by applying a directed surface structure that allows lateral air escape. The transfer images are also distributed, because they appear in essence always on the wave ridges of the surface structure, more evenly throughout the entire surface of the sheet and, thus, the sheet obtains a more homogeneous appearance. .

The directed generation of such a surface structure determines the use of additional equipment in a coating machine. The quality of the structure, that is, the depth of the roughness, the appearance, the average layer thickness of the upper sheet of the composite element, is controlled by machine adjustments and, as a general rule, the generation of a surface structure compared to a smooth surface of the sheet leads to a loss of layer thickness and, therefore, if necessary a loss of productivity. The application of a surface structure on a PVDC coated sheet due to surface irregularities is disadvantageous or even impossible when the composite element coated on the PVDC side is subjected to another lamination or coating process.

The newly coated and rolled composite sheet rolls relax over a few hours or days when sinking into rolled sections with less tension or in places with a smaller sheet thickness and tensing in places with higher sheet thicknesses. A consequence of the adhesion tendency of the newly coated PVDC is that due to the low sliding capacity between the sheet windings and the simultaneous relaxation, tensions appear along the surfaces of the sheet which, with a tendency to adhere too high , can even lead to destruction of material by separating the composite sheets in the individual sheets or layers.

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In DE 100 64 800 A1 micronized polyethylene waxes are described which are prepared by copolymerization of ethylene under high pressure conditions by using an aliphatic or alicyclic ketone as a regulator of molecular weight and subsequent micronization. Micronization should be understood as the grinding of substances up to particle sizes in the range of 1 | im up to a maximum of 100 | im. The substances are carried to the desired morphology by grinding or spraying. Numerous applications are known for micronized polyethylene waxes, for example as a support for printing inks, coatings, abrasives for dentifrices and addition for cosmetic preparations such as eye shadows, lipsticks or blusher.

Document DE 43 16 025 A1 refers to micronized polyethylene wax with an average particle size of 1 to 30 µm, suitable as a release agent for detaching the surface from sticky granules. Micronized polyethylene wax displays its effect already in reduced amounts of 0.01 to 2% by weight with respect to the granulate. Micronized polyethylene waxes are prepared by spraying a corresponding polyethylene wax melt with gases into a two stage nozzle.

From EP 0 403 542 B1 a polymer composition comprising a vinylidene chloride interpolymer formed from a mixture of monomers is known. The monomer mixture contains 60 to 99% by weight of vinylidene chloride and 40 to 1% by weight of at least one ethylenically unsaturated comonomer copolymerizable therewith. The vinylidene chloride interpolymer is mixed with a formulation package containing 0.1 to 95% by weight with respect to the total weight of the formulation package of an alkali metal salt or an alkaline earth metal salt of a weak acid , of an ethylene homopolymer and at least one plasticizer and a lubricant. Objects can be produced from the interpolymer of vinylidene chloride by casting, blowing, extrusion molding, coextrusion, lamination or calendering.

In EP 0 736 067 B1 a process for the stabilization of polyolefin mixtures containing PVDC and stabilized polyolefin mixtures containing PVDC is described. The plastics mixture comprises polyolefins and 0.05 to 20% by weight of PVDC and at least one phosphite or organic phosphonite as well as at least one metal salt of a fatty acid.

Document DE 198 32 500 A1 refers to a thermoformable composite sheet comprising at least one sheet containing cycloolefin copolymer and at least one thermoplastic sheet laminated on one side thereof. The thermoformable sheet is bonded by a solvent-free component adhesive with the cycloolefin copolymer-containing sheet. The thermoplastic sheet contains PVDC. The thickness of the entire sheet amounts to 100 to 500 µm, the thickness of the PVC sheet is in the range of 5 to 150 µm and the thickness of the COC sheet amounts to 50 to 400 µm. This thermoformable composite sheet is used for the production of blister packs. The thermoplastic sheet can also be selected from polyolefin, polyamide, polyester, polycarbonate, polystyrene, polyvinyl chloride and polyurethane.

Document DE 2012 349 discloses a dispersion and coatings prepared therefrom based on polyvinylidene chloride with reduced sealing jaw adhesion at temperatures around 120 ° C. The dispersion contains particles with a diameter in the range of 0.01 to 1 | i, the average particle size being preferably a factor 10 smaller than the thickness of the coating.

From WO 91/03518, co-polymers of extrudable vinylidene chloride with an increased resistance to thermal degradation are known. Materials intended for thermal processes such as extrusion, blow extrusion, injection molding, casting, calendering and vinylidene chloride copolymer based lamination include inorganic powder stabilizers, in particular Mg (OH) 2, with a size of particle in the range of 1 to 50 | i.

JP 57-059756-A discloses a coating based on a latex of copolymerized vinylidene chloride of 84 to 96% vinylidene chloride and 6 to 15% of a monomer, such as acrylic acid, methacrylic acid, acetate of vinyl or acrylonitrile and containing particles of a polyolefin with an average diameter of 1 to 20 | im, the thickness of the coating being found with respect to the average particle diameter in a ratio of 0.5 to 1. The coating is intended for paper and sheets for food packaging, the sheets being composed of materials such as polypropylene, poly (ethylene terephthalate), polyamide or cellulose derivatives.

JP 57-059757-A describes a coating containing olefin particles of a latex of copolymerized vinylidene chloride of 70 to 85% by weight of vinylidene chloride and 30 to 15% by weight of vinyl chloride as well as minus another monomer, finding the ratio of vinyl chloride to the monomer between 5:25 and 28: 2. Polyolefin particles have an average size of 1 to 20 | im. The thickness of the coating amounts to 0.5 to 1 times the particle size. The coating is intended for paper and sheets for food packaging, the sheets being composed of materials such as polypropylene, poly (ethylene terephthalate), polyamide or cellulose derivatives.

The aim of the invention is to create a coating for composite elements, in particular composite sheets having reduced coefficients of static friction and sliding for the improvement of the sliding properties of the composite sheet and that facilitate the handling of the composite sheets that are they have to

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coating on the machines and their subsequent processing on corresponding machines.

This objective is achieved by a composite sheet, according to claim 1, with a coating based on polyvinylidene chloride, such that particles of polymers, natural substances, modified natural substances, inorganic materials or mixtures are contained thereof in polyvinylidene chloride.

The density of the particles in this respect is in the range of 0.1 to 2.0 g / cm 3 and the average particle diameter in the range of 1 | im to 100 | im.

Suitably, the largest particle diameter is equal to or greater than the thickness of the PVDC layer.

In a further refinement of the invention, the particles are selected from a group containing HDPE, LDPE, LLDPE, polypropylene, PVDC, PVC, polyamides, polyurethanes, polyacrylates, polystyrenes, polyacrylonitriles, acrylonitrile-butadiene-styrene (ABS), polytetrafluoroethylene (PT) ), synthetic resins, hard waxes, mixtures and copolymers thereof.

In a configuration of the invention, the particles have a surface coating of one of the polymers of the group HDPE, LDPE, LLDPE, polypropylene, PVDC, PVC, polyamides, polyurethanes, polyacrylates, polystyrenes, polyacrylonitriles, acrylonitrile-butadiene-styrene polymers ( ABS), polytetrafluoroethylene (PTFE), synthetic resins, hard waxes, mixtures and copolymers thereof.

The other configuration of the invention results from the features of claims 2-11 and 20-21.

The process for the production of such a composite sheet, according to claim 12, with a polyvinylidene-based coating for strip-shaped materials is characterized in that a PVDC dispersion is provided to which the particles are added directly by dosing or a dispersion of particles with agitation. Suitably, the particle dispersion is prepared by stirring a particle powder in water without or with one or more emulsifiers. Advantageously, pigment distribution agents or other dispersion aids are added to the dispersion of particles. In an improvement of the process, the mixture of dispersion of PVDC and particles is applied as the uppermost layer on a web-shaped material and dried.

In particular, a dispersion of PVDC with 5 to 80% by weight of PVDC and a dispersion of particles with 10 to 95% by weight of particles are mixed together.

The other configuration of the process results from claims 19 to 21.

The coating is used for coating a PVDC layer of an element composed of several layers of PVDC sheet, adhesion promoting agent and supporting sheet as well as of an element composed of several layers of PVDC sheet, favoring agent of adhesion, polyethylene, adhesion promoting agent and support sheet. A PVDC sheet means a PVDC sheet on which a dispersion of PVDC in previous work cycles has already been applied as the base layer. They are other elements composed of several layers of sheets coated with PVDC PVC / PE / PVDC / PVDC + HDPE / PE / PVC; PVC / COC / PVDC / - PVDC + HDPE; PVC / PVDC / PVDC + HDPE / PE. Such sheets are applied, among other things, for the production of blister packs.

The inclusion of polymer particles, preferably of HDPE micronized in the uppermost layer of polyvinylidene copolymer of composite sheets, eliminates or greatly reduces the difficulties set forth above and the production processes for these Composite sheets become more simple and effective. These polymer particles serve as a separator between the windings of a sheet and improve the sliding properties of the PVDC surface of the sheet web.

Suitable polymers for these particles in the liquid and powder form are those that are quite compatible with the respective dispersion of PVDc, do not have an abrasive effect and in particular are not substantially harder than the PVDC coating or the side bottom of the support or base sheet on which the PVDC coating is applied. If the particles are harder than the remaining sheet surfaces of a composite element, the surface of the particles should be, as far as possible, smooth and, ideally, spherical. Ideally, the particles have a coefficient of static friction and slippage as little as possible. The particles, at the usual drying temperatures for PVDC drying of up to 100 ° C, should not form films and during drying they should not "melt" with the PVDC, that is, they should not form a film of homogeneous PVDC polymer / particles . Instead, the polymer particles must protrude from the PVDC layer and thus fulfill their function as a separator. Additionally, the particle material must have a diffraction index similar to the PVDC, so that the lowest possible opacity appears in the PVDC particle layer. The density of the particle material is in the range of 0.1 to 2.0 g / cm3, in particular in the range of less than / equal 1.30 g / cm3 and is preferably less than 1 g / cm3 in such a way. that a float is favored in the dispersion of particles and, therefore, the projection from the surface of PVDC. Properly, the largest particle diameter is greater / equal to the thickness of the coating. The average particle diameter of

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The particles must also be adjusted to the application system so that irregularities in the particle content cannot appear due to too large particles or a heterogeneous application. In order not to negatively influence the barrier effect of the PVDC coating, the particles should not be porous. The barrier effect has to be as much as possible in the field of application of the composite sheet or the composite element.

Particles include, in principle, all polymers that fully or partially meet the above conditions, for example: HDPE, LDPE, LLDPE, PP, PVDC, PVC, polyamides, polyurethanes, polyacrylates, polystyrenes, polyacrylonitriles, ABS, PTFE, waxes hard, synthetic resins among others as well as mixtures and copolymers thereof. Likewise, particles having a suitable surface coating can be used. The core materials of such coated particles are, for example, polymers of the above enumeration, as well as natural substances such as cellulose, natural waxes, poly (hydroxyalkanoic acids), shellac, modified natural substances such as casema derivatives and condensates of Casema, cellulose derivatives, such as, for example, cellulose acetate and cellulose nitrate or inorganic substances such as, for example, silicon dioxide, silicates, aluminum oxide, titanium dioxide. As coating materials, the aforementioned polymers or correspondingly suitable different surface coatings, such as silanes, siloxanes, ormoceras (organically modified ceramics), ceramic materials can be used.

It is also possible to use particles that are purely inorganic in nature, such as, for example, silicon dioxide, silicates, aluminum oxide, titanium dioxide and possessing the properties indicated above.

If the particles are of polymeric origin, they can be prepared by polymerization, polycondensation, polyaddition, analogous reaction to polymer or mixture of prefabricated polymers. The particle form and division are usually carried out directly during the polymerization, for example, suspension or emulsion polymerizations, or by subsequent mechanical division and / or suspension and stabilization in a carrier liquid. Inorganic particles can be prepared, for example, by grinding natural substances or synthetically. Surface coatings can be applied on such particles.

In the case of the application of particles, the percentage part of particles in the dry coating is usually in the range of 0.1% by weight to 10% by weight. For particles in the form of micronized HDPEs, for example, a dry portion of about 0.2 to 2% by weight of micronized in the dry coating mass is particularly effective.

For the production of such PVDC coatings containing particles, the dispersion of PVDC prior to application on a web-like material is mixed with stirring with a corresponding amount of the suspension or dispersion of particles until the suspension has been mixed or homogenous dispersion with the PVDC dispersion. For this a commercially available agitator is used, which does not apply shear, for example, a vane agitator. Next, the mixture is applied with a usual application mechanism for PVDC coatings on the material to be coated and dried. If the size of the formula has been correctly chosen and compatibility with the PVDC dispersion is given, then in relation to the coating and / or drying behavior no difference can be found with respect to the unmodified PVDC dispersion. The finished coating material is characterized by the following essential procedural and product advantages:

- The static and sliding friction of the surface of the coated material is, in particular in the newly coated state, essentially less than that of the unmodified PVDC coating.

- The tendency for adhesion of newly coated material is, although the surface of PVDC is not structured, clearly reduced. In this respect, "unstructured" means a surface from which particles stand out, however, where the surface does not form or form wave valleys or wave crests.

- They are intensely reduced or even completely missing adhesion traces due to prints on the back side of the next sheet winding on the roll sheet.

- Despite the lack of surface structuring, due to the effect of separating the particles, an aeration of the sheets or the roll of material is guaranteed. The included air can lead to deformations of sheets or material and due to the tendency of adhesion of fresh PVDC to a dullness of the irregular surface of the sheets.

- Thanks to the reduced static friction of the PVDC surface, the shear forces that occur due to the relaxation movements of the newly coated roll material, directed in parallel with respect to the surface of the material, can be better relaxed due to the sliding of the PVDC surface over the next sheet winding. This avoids destruction of material that is caused in the case of less slippery PVDC surfaces due to delamination caused by shear forces between the PVDC layer and the base support.

- The frictional resistance of flat sheets coated with PVDC in machine parts of thermoforming machines that are used for the production of blisters from flat sheets is reduced. Therefore, lamellar throttles are completely reduced or eliminated due to too high band tensions.

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- The filling of packaging products in the form of tablets or capsules is considerably improved, because they can slide better inside the blister cavities, due to the intensely reduced coefficients of static friction and sliding. In particular, the gelatin capsules tend, in the case of the use of unmodified PVDC, not to slide inside the cavity, to be placed upright in the cavity or even to jump out of the cavity. This leads to a sealing station directly subsequent to the packaging station to soiling by crushed packaging products and, therefore, to longer cleaning procedures.

- In addition, it is advantageous that no additional equipment is needed on the machine side for surface structuring or special procedures. The surface properties depend exclusively on the formulation and therefore can be adjusted safely and are easy to reproduce.

- Due to the coating, a flat smooth surface is generated which, aesthetically, is more pleasant than a structured surface.

- The flat surface makes it possible to adjust a higher layer volume than in the case of a structured surface for the higher PVDC layer, since the maximum layer thickness that can be dried in a structured layer is predefined by the highest points of the structure, that is, the peaks of the wave ridges, while in the case of a flat surface the thickness of the layer that can be dried is as large as the maximum thickness of the layer that can be dried from the structured layer , however, unlike it does not present any wave valley, but has a constant layer thickness continuously.

It is also advantageous that a surface modified in this way is very slippery with respect to the back side of the coated sheet and with respect to the cavities of the molding tool. This leads to, on the one hand, unstacking of the blister sheets with the cavities stacked on each other, finished forming, not yet filled, for example, in the form of trimmed pieces of blister format, or, on the other hand The release of newly formed blister concavities from the deep drawing tool, provided that the modified PVDC side is used on the outer side of the blister concavity, is possible with a clearly lower strength / force application. In the first case, this leads to faster unstacking and, therefore, to an increase in productivity, in the second case, to a more free operation of alterations of the blister machine and, therefore, to an increase in performance.

The invention is explained in more detail by means of the drawings. They show:

Fig. 1, in a schematic representation of the cut, a usual PVDC coating of a sheet composed of PVDC sheet / support sheet with structured PVDC surface and

Fig. 2, in a schematic representation of the cut, a coating according to the invention of PVDC, mixed with particles, on a sheet composed of PVDC sheet / support sheet.

The composite sheet 6 shown in the cross-section in Figure 1 comprises a support or base sheet 4, an adhesion favoring agent 3 and a PVDC sheet 2. The adhesion favoring agent 3 establishes the joining of the sheet of PVDC 2 with the support sheet 4. On the upper side of the PVDC sheet 2 a PVDC coating 7 having a structured surface 5 is applied, such that the layer thickness of the PVDC coating along The width of the composite sheet 6 is irregular and contains wave crests and wave valleys.

The composite sheet 1 represented in the cross-section in Figure 2 is composed of a support or base sheet 11, an adhesion promoting agent 10, a PVDC sheet 9 and a PVDC coating 8, in which they are included 12 HDPE particles. The particles 12 have different particle diameters, the average particle diameter amounts to 6 to 8 µm and is suitable for a dispersion of HDPE that leads to a coating up to 6 µm thick. The largest particles have a diameter of approximately 12 | im.

For a layer thickness of 12 | im, the average particle size is in 12 to 13 | im. The largest particles have a size of approximately 17 | im. A quantity of particles 12 protrudes from the flat surface 13 of the coating 8 and acts as a separator between the windings limiting each other of a rolled composite sheet 1.

Mixing a PVDC dispersion with an HDPE dispersion

The following examples serve to explain the invention in more detail without limiting the scope of protection of the invention characterized in the claims. 1000 l of PVDC dispersion coating and a commercially available or freshly prepared HDPE dispersion are mixed respectively. The PVDC dispersion has a part of 55% by weight of PVDC with respect to the total mass of the PVDC dispersion and a density of 1.29 g / cm3. In the HDPE dispersion, the HDPE portion amounts to 65% by weight with respect to the total mass of the HDPe dispersion and the density at 0.96 g / cm3.

The desired amount of PVDC dispersion is disposed in a 1000 l container and stirred uniformly. The calculated amount of HDPE dispersion is added during the non-foaming agitation of the PVDC dispersion in a fine stream and the mixture is stirred for another 5 to 10 minutes. How

HDPE dispersion can be used a commercially available finished dispersion or a freshly prepared dispersion of an HDPE powder that is prepared by corresponding agitation of the particulate powder in water with or without the aid of one or more emulsifiers, of distribution agents of pigments or other dispersion aids, of anionic surfactants. It is also possible the direct addition of an HDPE powder in the PVDC dispersion 5, taking into account in particular that no agglomerates occur that can cause non-uniform coating thicknesses.

Example 1

The part of the dispersion of HDPE was 1% by volume with respect to the total volume (in liters) of the coating. The corresponding parts by weight% of the PVDC and HDPE in the dried film are calculated as follows:

image 1

% PVDC part of PVDC of the dried coating in% by weight

% PE part of HDPE of the dried coating in% by weight

VpDdc volume used for dispersion of PVDC

Vpe volume used for dispersion of HDPE

pPVDC PVDC dispersion density

pPE HDPE dispersion density

FKpvdc solids part of the PVDC dispersion in% by weight

FKpe solids part of the dispersion of HDPE in% by weight

 Component

 Amount of dispersion (I) Dry part,%,% by weight

 PVDC dispersion

 990 99.12

 HDPE dispersion

 10 0.88

Example 2

15 The part of the dispersion of HDPE was 2% in volume with respect to the total volume (in liters) of the coating

 Component

 Amount of dispersion (I) Dry part,%,% by weight

 PVDC dispersion

 980 PVDC 98.24

 HDPE dispersion

 20 HDPE 1.76

Next, the measured coefficients of static friction and slippage of a conventional composite sheet with pure PVDC coating, as described in Figure 1, and of the sheets according to Examples 1 and 2 are contrasted. The friction force measurement was made with an aluminum specimen that is coated with hard gelatin.

The measurement conditions were as follows:

Test speed:

Test Mass:

Material:

Test tube coating:

Air humidity:

Process:

Age of the PVDC coatings of the three sheets respectively:

5 mm / min 200 g

aluminum, hard gelatin anodized

50% relative humidity analog to ASTM D 1894

10 days

 Material

 Static friction coefficient Sliding friction coefficient

 PVDC without particles, however with surface structure

 1.04 Not measurable since no continuous movement appears

 PVDC with 1% by volume of HDPE

 0.41 0.21

 PVDC with 2% by volume of HDPE

 0.29 0.19

A strong indirect dependence on the static friction coefficient of the HDPE part in the coating according to the invention is shown. With a growing part of HDPE the static friction coefficient 5 is reduced. With the formula ((HRKop -HRKp) / HRKop) x 100%, in which HRKop is the static friction coefficient of the PVDC coated composite sheet without particles in the PVDC coating and HRKp is the static friction coefficient of the PVDC coated composite sheet with particles in the PVDC coating results in reductions of the static friction coefficient HRKp of 61% and 72% with a volume portion of HDPE of 1% or 2%.

10 Processing of composite sheets

In processing, the following advantages are achieved with respect to PVDC coatings that do not contain particles:

- Better demoulding of the deep blister drawing mold when the PVDC coated composite sheet is processed outside with the PVDC coating.

15 - lower throttling of the web because of lower friction resistance with respect to parts of

machine.

- better packaging properties of gelatin capsules in blister packs manufactured from the composite sheets (PVDC side towards the filling product).

- lower tendency of composite sheets to adhere to hot parts of machines.

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Claims (20)

5 10 fifteen twenty 25 30 35 40 Four. Five fifty 1. Composite sheet (1) comprising a support sheet (11), adhesion promoting agent (10), a PVDc sheet (9) and a coating (8) applied on the PVDC sheet (9) based of polyvinylidene chloride, characterized in that particles (12) of polymers, natural substances, modified natural substances, inorganic materials or mixtures thereof are contained in the polyvinylidene chloride of the coating (8), the density of the particles (12) are in the range of 0.1 to 2.0 g / cm3, the average diameter of the particles (12) is 1 to 100 | im, a certain number of the particles (12) protrude from the coating (8) and the largest particle diameter is equal to or greater than the thickness of the coating (8). 2. Composite sheet (1) according to claim 1, characterized in that the density of the particles (12) is less than / equal to 1.30 g / cm3, in particular less than / equal to 1 g / cm3. 3. Composite sheet (1) according to claim 1, characterized in that the particles (12) are selected from a group containing HDPE, LPDE, LLDPE, polypropylene, PVC, PVDC, polyamides, polyurethanes, polyacrylates, polystyrenes, polyacrylonitriles, acrylonitrile-butadiene-styrene polymers (ABS), polytetrafluoroethylene (PTFE), synthetic resins, hard waxes, mixtures and copolymers thereof. 4. Composite sheet (1) according to claim 3, characterized in that the particles (12) have a surface coating of one of the polymers of the HDPE, LPDe, LLDPE, polypropylene, PVC, PVDC, polyamides, polyurethanes, polyacrylates group , polystyrenes, polyacrylonitriles, polymers of acrylonitrile-butadiene-styrene (ABS), polytetrafluoroethylene (PTFE), synthetic resins, hard waxes, mixtures and copolymers thereof. 5. Composite sheet (1) according to claim 4, characterized in that the particles (12) have a dry part of 0.1 to 10% by weight with respect to the dry weight of PVDC. 6. Composite sheet (1) according to claim 5, characterized in that the particles (12) have a dry part of 0.3 to 8% by weight with respect to the dry weight of PVDC. 7. Composite sheet (1) according to claim 5, characterized in that the particles (12) have a dry part of 0.2 to 2% by weight with respect to the dry weight of PVDC. 8. Composite sheet (1) according to claim 1, characterized in that the particles (12) are included in powder form in the PVDC. 9. Composite sheet (1) according to claim 1, characterized in that the coating (8) is liquid and is composed of a mixture of an anionic PVDC dispersion and an anionic dispersion of micronized particles. 10. Composite sheet (1) according to claim 9, characterized in that the anionic dispersion is composed of micronized particles, one or more emulsifiers, anionic surfactants, pigment distribution agents and dispersion aids. 11. Composite sheet (1) according to claim 3, characterized in that the particles (12) are composed of HDPE. 12. Method for the production of a composite sheet according to one of claims 1 to 11, comprising the provision of a web-shaped material comprising a support sheet, adhesion promoting agent and a PVDC sheet and coating of the PVDC sheet with a dispersion based on polyvinylidene chloride, characterized in that a PVDC dispersion is arranged in which the particles are directly agitated or a particle dispersion is agitated. 13. Method according to claim 12, characterized in that the dispersion of particles is prepared by stirring a particle powder in water without or with one or more emulsifiers. 14. Method according to claim 12, characterized in that pigment distribution agents or other dispersion aids are added to the dispersion of particles. 15. Method according to claim 12, characterized in that the mixture of dispersion of PVDC and particles is applied as the uppermost layer on the web-shaped material and dried. 16. Method according to claim 15, characterized in that a dispersion of PVDC with 5 to 80% by weight of PVDC and a dispersion of particles with 10 to 90% by weight of particles are mixed together. 17. Method according to claim 16, characterized in that a dispersion of PVDC with 30 to 70% by weight of PVDC and a dispersion of particles with 40 to 70% by weight of particles are mixed together. 18. Method according to claim 15, characterized in that a PVDC dispersion of 80 to 99% by weight and 1 to 20% by weight of particle dispersion is mixed together. 19. Method according to claim 17, characterized in that the particle dispersion is a dispersion of PVDC-HDPE with a dry portion of 0.50 to 3.0% by weight of HDPE in the mixture of dispersion of PVDC and HDPE. 20. Composite sheet (1) according to one of claims 1 to 11, characterized in that the coating (8) containing particles (12) is applied on a PVDC sheet of a composite element multi-layer PVDC sheet, adhesion favoring agent, polyethylene sheet, adhesion favoring agent, support sheet; PVDC sheet, adhesion promoting agent, cycloolefin copolymer (COC), adhesion promoting agent, PVC; or PVDC sheet, adhesion favoring agent, PE, adhesion favoring agent, PVC. Use of the composite sheet (1) according to one of claims 1 to 11 in a composite element Multi-layer PVC / PE / PVDC / PVDC + HDPE / PE / PVC sheet.